NSES Content Standard B 
Physical Science: Transfer of energy
Grades 5-8, page 155

Heat moves in predictable ways, flowing from warmer objects to cooler ones, until both reach the same temperature.

Benchmark 4E The Physical Setting: Energy Transformations
Grades 3-5, page 84
When warmer things are put with cooler ones, the warm ones lose heat and the cool ones gain it until they are all at the same temperature. A warmer object can warm a cooler one by contact or at a distance.